LFunCalc is a function calculator that formulas are displayed and entered as a list. Just after a formula is entered, the result is displayed without tapping enter key. A formula name is assigned to each input line and can be referenced as a variable in the following formulas. When a formula is changed, the value of the other formula referencing it is updated too. LFunCalc is also useful as a tool of parameter study. Note) LFunCalc is not a spreadsheet application.